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About Jan Shim, MD

Dr. Shim strives to provide her patients with the very best care in digestive diseases and gastrointestinal endoscopy. Her mission is to deliver compassionate, high quality, and comprehensive care through an unparalleled patient experience.

Dr. Shim provides compassionate and reliable care to all of her patients. She prioritizes delivering quality care and cutting-edge treatments. She is on staff at both Westside GI LLC and Hudson in New York, NY, and Hudson Crossing ASC in Fort Lee, NJ.

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Colonoscopy

A colonoscopy is now the gold standard used to detect or prevent individuals from getting colon cancer. Adults starting at age 45 years are strongly recommended to have a colonoscopy or some other test to screen for colon cancer.

Capsule Endoscopy

During the procedure, a patient swallows a vitamin-sized pill with a camera inside (pill camera). Transported smoothly and painlessly through the GI tract by the body’s own natural peristalsis, the video pill capsule transmits images of different parts of your intestine, such as the small intestine and the esophagus.

ERCP

An endoscopic retrograde cholangiopancreatography, more commonly known as ERCP, is an endoscopic procedure that is also combined with X-rays. ERCP is very much like a typical upper GI endoscopy; however, your gastroenterologist will inject a dye during the procedure, which highlights problems in certain digestive organs through X-ray technology.

Flexible Sigmoidoscopy

A sigmoidoscopy is an internal exam of the lower part of the large intestine (colon) using a short, thin, flexible, lighted tube with a camera at the tip. This procedure helps determine the cause of abdominal pain, rectal bleeding, changes in bowel habits, chronic diarrhea, and other intestinal problems.

Hemorrhoid Treatments

Two of the most common treatments for hemorrhoid removal are hemorrhoid banding, which cuts off blood flow to the hemorrhoid, and infrared coagulation (IRC) therapy, which uses infrared light to shrink and shrivel hemorrhoids. The treatment method depends highly upon whether the hemorrhoids are external (around the anus) or internal (in the rectum).

Upper Endoscopy

An endoscopy is a very common and safe procedure that is used to examine the esophagus, stomach, and upper part of the small intestine, known as the duodenum, to get a closer look at what may be causing symptoms.

Celiac Disease

Celiac disease is an autoimmune disease where a patient’s immune system abnormally responds to the ingestion of gluten. It is estimated that 1 in 100 people worldwide is affected by celiac disease. However, up to 2.5 million people in the United States may have celiac disease and not know it, as the symptoms range from mild to severe.

Constipation

Constipation is defined as having a bowel movement fewer than three times per week. With constipation, stools are usually hard, dry, small in size, and difficult to eliminate. Some people who are constipated find it painful to have a bowel movement and often experience straining, bloating, and the sensation of a full bowel.

GERD

Gastroesophageal reflux disease (GERD) is a more serious form of gastroesophageal reflux (GER) which is common. GER occurs when the lower esophageal sphincter (LES) opens spontaneously, for varying periods of time, or does not close properly, and stomach contents rise up into the esophagus.

Hemorrhoids

Hemorrhoids are swollen veins in the anal canal. This common problem can be painful and can be caused by too much pressure on the veins in the pelvic rectal area. Normally, tissue inside the anus fills with blood to help control bowel movements, but if you strain or sit on the toilet a long time to move stool, the increased pressure causes the veins in this tissue to swell and stretch.

Inflammatory Bowel Disease + Crohn's Disease & Ulcerative Colitis

Inflammatory bowel disease (IBD) encompasses a set of gastrointestinal diseases where parts of the digestive tract are chronically inflamed by a dysfunctional interaction immune system. Hereditary factors and an abnormal interaction between microorganisms and the immune system are felt to play a role.

Irritable Bowel Syndrome

It is estimated that 10 to 15 percent of Americans have Irritable Bowel Syndrome (IBS). IBS is a functional GI disorder that refers to a group of symptoms that affect the digestive tract, often resulting in abdominal pain, bloating, or cramping. However, some people with IBS have no symptoms at all.

Diet & Nutrition

Nutrition plays a paramount role in gastroenterology as it directly influences the health and functioning of the digestive system. We have nutritional resources available to help understand the role adequate nutrition plays in preventing and managing various digestive disorders.

Infusion Therapy

Infusion Therapy is a medication used to treat inflammatory bowel disease(IBD), which includes Crohn’s disease and ulcerative colitis (UC). It is not a first-line treatment method for IBD but instead a medication given to patients who haven’t responded to more common IBD treatments. Patients require infusions approximately three to six times a year, depending on the type of medication. Infusion Therapy works well at arresting symptoms and reducing disease severity, sometimes putting IBD into remission.

What Our Patients Say About Dr. Shim

Blogs

Colon Cancer

Colorectal Cancer and Stool: Red Flags to Be Aware Of

Your stool can reveal a surprising amount about your digestive health, and paying attention to it is one of the simplest ways to catch a problem early. While most changes

July 15, 2026

Diet

Best and Worst Protein Sources for IBS

Protein is essential for energy, muscle, and overall health, but for people with irritable bowel syndrome (IBS), how you get that protein can make the difference between a comfortable day

July 8, 2026

Constipation

Can Constipation Make You Nauseous?

If you have ever felt queasy during a bout of constipation, you are not imagining the connection. While constipation is usually thought of as a lower-digestive problem, it can also

July 1, 2026

Ulcers

Signs of Stomach Ulcers

Stomach ulcers, also known as peptic ulcers, are painful sores that develop in the lining of the stomach or the first part of the small intestine. These ulcers can cause

June 18, 2026

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